Trama

A tourist spends the night in a derelict Spanish villa seemingly held in the supernatural grip of an eccentric butler, who resembles a depiction of the Devil she had seen on an old fresco.

During the sightseeing in Toledo, Spain, the tourist Lisa Reiner sees an ancient painting of the devil on the wall and leaves her group for a moment; however she gets lost in the narrow streets. Later she gets a lift with the wealthy Francis Lehar and his wife Sophia. However, their car breaks and stops in front of an old manor. While the driver George tries to fix the car, the trio is hosted by the blind owner and her son Maximilian who invites Lisa to spend the night in the mansion. During dinner, they are served by the butler Leandro that resembles the image of the devil of the painting. Lisa seems to be living a strange nightmare, recalling her love from a past life, and trapped in the house with that bizarre family.—Claudio Carvalho, Rio de Janeiro, Brazil

[note: this synopsis is only for Mario Bava's true and original Lisa and the Devil (1973), not the re-shot, re-edited version 'The House of Exorcism' (1975)]

Lisa Reiner (Elke Sommer) is a young American woman vacationing in Spain with some friends of hers. During a stop in a small town square with her tour group, Lisa grows to admire a fresco of the devil carrying a dead man's body which her tour guide describes as the devil carrying away lost souls back to Hell. As her group disperses, Lisa hears a beautiful piece of music. She leaves her companions and traces its source to an elaborate music box in a little antique shop just outside the main square. While inside the shop, she encounters a strange man (Telly Savalas) purchasing parts of a life-size mannequin. After making eye contact, Lisa is startled when the man bears an uncanny resemblance to the devil depicted in the painting. The man's peculiar behaviour distresses Lisa, so she flees from the shop to rejoin her friends.

However, she becomes hopelessly lost in the maze of backstreets of the town. Though she has only walked a short distance beforehand, the back streets and alleyways seem totally alien to her. The locals refuse to give her directions, as side streets lead to dead ends. Lisa runs into the mysterious man a second time, though this time he is carrying a full-length, life-sized mannequin eerily similar to the painting depicted in the main square, as well as carrying the music box still playing the haunting tune. Introducing himself as Leandro, he gives Lisa some vague directions back to the main square, then walks around a corner and disappears. But the direction that Leandro points to the main square leads only to more unfamiliar streets. Next, Lisa encounters a strange man who looks a lot like the mannequin that Leandro was carrying. These bizarre coincidences begin to terrify Lisa, and the stranger acts as though she is his long-lost lover. Frantic, Lisa pushes him away and the man falls down a flight of stone steps, apparently dead. Lisa runs off in a panic.

Night falls on the village, and Lisa remains lost. However, her luck seems to be improving when she hitches a ride in a old vintage 1940s limousine which contains Francis Leher (Eduardo Fajardo) and his wife Sophie (Silvia Koscina) whom are driving through the village with their chauffeur George (Gabriele Tinit). But their limousine soon breaks down just outside a old villa on the town's outskirts. The four travelers push their car into the villa grounds and knock on the front door asking for assistance. The villa turns out to be occupied by an elderly blind countess (Alida Valli), and her neurotic son Maximilian (Alessio Orano). When Maximilian spots Lisa, he becomes convinced that she is the reincarnation of a woman that loved and lost. Maximilian implores his mother to allow the four stranded tourists to stay for the night while he helps the chauffeur repair the car's engine. Though the villa is well-appointed, it has a strange atmosphere. Lisa is subsequently shocked to discover that Leandro is the family butler, who also recognizes her from their brief meetings earlier, and seems a little too friendly to Lisa.

As Leandro settles Lisa, Francis and Sophie, and George into their living quarters for the night, Lisa jumps with fright when she sees the same man from the village who tried to attack her, staring at her through the window. Lisa tries to get away from the house, but her departure is thwarted by Maximilian, who begs her to stay. As she feels some attraction to the young man, as well as pity for him, Lisa relents.

The four travellers are settled down to dinner, while the food is served by Leandro. Lisa further notices the weird atmosphere of the place, when Maximilian continues to remind Lisa that she has a resemblance towards his lost lover, Elena. But Francis and Sophie's relationship becomes more strained as dinner progresses. Francis' cold, dispassionate nature forces Sophie to walk away from him, and she falls into the arms of George, whom they have quick passionate sex. A short while later, George is found dead, with a pair of scissors plunged into his throat. Sophie immediately assumes that her husband did it, and she flees outside into the car where she starts it up, When Francis comes out to stop her from leaving, she runs over him over and over again. But upon returning into the house, Sophie is killed by Maximilian in a hurtful, gory way. It was Maximilian who murdered the chauffeur to prevent Lisa from leaving.

With the meddling strangers out of the way, Maximilian turns his attention to Lisa where it's revealed that the man who pursued Lisa in the village is actually Maximilian's stepfather Carlos (Espartaco Santoni). Like Maximilian, he had previously fallen in love with Elena, the woman displayed in a few old photographs who bears an amazing resemblance to Lisa. Carlos had abandoned the countess and ran off with Elena, who was also Maximilian's lover. Before she had a chance to join him, Maximilian had murdered Elena and stored her body in a concealed room so he could continue to have her, even in death. Apparently when Carlos returned to the village, he assumed after seeing Lisa that she was Elena. Now that Maximilian had murdered Carlos, he puts him display in an open coffin in the parlor so that nobody can take Lisa away from him.

At this point, Lisa still has no idea that Maximilian is completely deranged, and on top of that, she's still being casually nice to him. When Maximilian decides to share his secret with Lisa about his lost love Elena, he takes her to the concealed room, and shows her Elena's skeletal remains, Lisa finally then backs away in horror and rejects Maximilian. But rather than kill her, he chloroforms Lisa and puts her in the bed next to Elena's remains. Maximilian strips Lisa naked and tries to have sex with the unconscious woman. But in his twisted state of mind, he feels that the skeletal remains of Elena is mocking him and he cannot perform. Apparently deciding that in order to consummate the relationship, he will have to marry her.

Maximilian meets his mother in the parlor who's paying respects to her dead husband where he tells her of his intentions. The Countess, jealous of the hold Elena, in the form of Lisa, continues to hold over the men in her life, demands that Maximilian kill Lisa and dispose of her and the rest of the bodies before the police show up looking for her and the other murder victims. But Maximilian's devotion to Lisa is complete, and rather then get rid of her, he stabs his mother dead as she stands by the coffin that contains Carlos' body.

All of these events are observed by Leandro, whose presence seem to haunt the villa, and who seems to be orchestrating the bizarre occurrences as some kind of sick game. Unsettled by this act of matricide, Maximilian rushes about the house looking for Leandro who, for once, is nowhere to be found. Instead, Maximilian finds the bodies of all his victims, including the skeletal Elena, seated at the dinner table looking at him. He turns around and sees his undead mother shambling towards him. In shock, Maximilian recoils backwards, only to fall out a second floor window, and onto the spikes of a gate. Emerging from behind the body of the dead Countess, Leandro remarks, "oh, it slipped".

The next morning, Lisa wakes up, naked and in unfamiliar surroundings. Though it seems to be the exact same concealed room, it is now infested with vegetation and she is alone with no bodies anywhere. Putting her clothes back on, Lisa walks through the house and finds that its entirely deserted. In fact, it looks that nobody has lived in the house for a long time. Confused, but somewhat relieved that the entire night's experience was apparently nothing but a bad dream, Lisa leaves the house and runs into a group of schoolgirls playing ball in the street. The balls rolls in her direction and she catches it. One of the the girls points to Lisa and proclaims her a ghost because nobody has lived in the villa for a hundred years. The girls run away screaming. Lisa walks around a little and within minutes finds herself back in the town square from the beginning of the movie. She is observed by Leandro a short distance away who is being given a mannequin likeness of her.

Lisa takes a taxi to the airport and enters a plane. After the plane takes off, Lisa notices the she is the only passenger. She searches section after section, only to discover the dead bodies of Maximilian, the Countess and all the others in the first class compartment. Frantically, Lisa makes her way to the cockpit where she opens the door and discovers that Leandro is the pilot, who lets out a devilish laugh. Lisa transforms into a ghastly pale mannequin and slumps to the floor.